The present invention relates to cylindrical or barrel type crushing machines. More particularly, the present invention relates to crushing machines having a rotatable housing with crushing members contained inside.
The function of crushing machines, to which the present invention relates, is to crush stones, steel slags, gravel, or sand, and to screen these materials to provide a desired size of particulate. The crushing machine includes driving means for rotating the housing, thereby engaging the crushing members with the materials in the housing.
Prior art conventional crushing machines exist for pulverizing rocks or other materials into sand or the like. These crushing machines are of a barrel type. Barrel type crushing machines include both side walls and multiple rods installed in a rotating cylinder. The rotating cylinder, in turn, has an inlet port in the side of said wall, and a discharge port in a peripheral wall.
One disadvantage with the conventional barrel type crushing machine is the time necessary to maintain and adjust a trunnion which receives the rotating cylinder. Another disadvantage is that installation requires special technical skills.
Moreover, since the machine is used in dusty areas with a rotating cylinder driven by gears and/or belts and supported with free rotation by bearings at both ends, the dust impedes and damages the exposed bearings, causing the metal to burn and grease to leak.
Another disadvantage with the conventional barrel type crushing machine is the necessity of providing a pit under the discharge port of the rotating cylinder in order to place an equipment such as a belt conveyor for transferring the crushed material. The necessity for providing a pit increases the cost required for installation and maintenance of the crushing machine.
Japanese Patent No. 1,003,597 shows a sand machine which has side walls on both sides of a rotating cylinder. The inlet port for stones is in one side wall and a discharge port for ejecting the crushed sand is in the other side wall. Two pairs of semicircular rings are mounted on the periphery of the rotating cylinder. The lower part of the rings rests on the rubber tires that are connected to a power source. The sand machine of this type is so designed that stones are charged into the rotating cylinder together with water, crushed by the rods inside, and then discharged from the discharge port.
In this particular type of machine, however, the rings have a diameter of only 1.5 times that of the rotating cylinder. As a result, the load applied on the rubber tires is large. Furthermore, the efficiency of transferring the power from the rubber tires to the rings is poor because the diameter of the rings is small.
Another drawback of this particular sand machine is the location of the discharge port. The discharge port is placed in one side of the side wall, and this makes it difficult to crush the stones or steel slags into the gravel of desired size. Even if the discharge port is moved to the center of the rotating cylinder, the cylinder is installed too low to place an equipment to transfer the discharged materials under the cylinder without making a pit, requiring a troublesome installation.
It is an object of the present invention to provide a crushing machine that dose not require expensive or frequent maintenance.
It is another object of the present invention to eliminate the effect of dust on the machine's performance.
Yet another object of the present invention to make it unnecessary to have a pit under the discharge port for allowing equipment under the machine.
A further object of the present invention is to increase the efficiency of the power transferred from the housing.
It is still further object of the present invention to place the discharge port in a position to effect ease of crushing stones or steel slags into the desired size.
Another object of the present invention is to decrease vibration of the housing, thereby preventing the internal crushing means from being displaced.
It is yet another object of the present invention to eliminate bearing and critical adjustment thereof.
It is also an object of the present invention to eliminate direct gearing between the housing and the driving means.